Segmented crusher liner

ABSTRACT

A CRUSHER OF THE GYRATED HEAD-TYPE HAVING A CRUSHING HEAD GYRATED BENEATH OR WITHIN A BOWL. THE MANTLE OF THE CRUSHING HEAD IS FORMED OF FACING PARTS OF A METAL HAVING A VERY HIGH RESISTANCE TO WEAR AND A BACKING OR SUPPORTING STRUCTURE HAVING LESS RESISTANCE TO WEAR BUT GREATER TENSILE STRENGTH AND ADEQUATE RESISTANCE TO FRACTURE.

United States Patent Jerome C. Motz Milwaukee, Wis.

Mar. 7, 1969 June 28, l97l Nordberg M anulacturiug Company Milwaukee,Wis.

Continuation-impart of application Ser. No. 617,282, Feb. 20, 1967, nowabandoned.

inventor Appl. No. Filed Patented Assignee SEGMENTED CRUSHER LINER 6Claims, 5 Drawing Figs.

US. Cl

Int. Cl Field of Search...

[56] References Cited UNITED STATES PATENTS RE. 16.923 6/1970 Curtis241/294 993,783 5/1911 Mason 241/295 2,594,080 4/1952 Shafter 24l/300X2,913,189 11/1959 Werner i 241/295 3,353,758 11/1967 Whaley 241/300Primary Examiner-Donald G. Kelly Attorney-Parker, Carter and MarkeyABSTRACT: A crusher of the gyrated head-type having a crushing headgyrated beneath or within a bowl. The mantle of the crushing head isformed of facing parts of a metal having a very high resistance to wearand a backing or supporting structure having less resistance to wear butgreater tensile strength and adequate resistance to fracture.

SEGMENTEI) CRUSHER LINER This is a continuation-in-part of Ser. No.617,282, filed Feb. 20, 1967, now forfeited.

SUMMARY OF THE INVENTION The present invention relates to wear takingbodies or members which may be used, for example, with cone or gyratorycrushers, in which a crushing head is employed with a surrounding bowlto define a crushing cavity. A typical crusher of this type is one inwhich the cone or head is gyrated within or beneath a bowl. Theparticular structures shown in the present application are wearing partsfor use in crushers in which a head is gyrated to cause the wearing partor mantle of thehead to move toward or away from the wearing part orliner of a surrounding bowl. The two wearing parts define a crushingcavity into which material is discharged from above to be reduced. Theliner and the mantle take the crushing wear, and with some materialsundergoing crushing this wear may be tremendous, for example, whereTaconite is being crushed. In any event, the liner and mantle wear away,and they may wear away very rapidly. The choice of materials for suchwearing parts has hitherto been limited, in usual commercial practice,to metals which have relatively poor wear-taking characteristics, butwhich have great toughness, to enable them to stand crushing stresseswithout breaking or cracking. In the industry, manganese steel has beena generally accepted material for bowl liners and mantles. Thismaterial, although tough, lacks the hardness of some other materials,and wears at a more rapid rate. On the other hand, the hard steels,which have the highest wear resistance, are prevailingly far morebrittle than manganese steel, and this brittleness involves the risk ofthe formation of cracks or breaks. Hence, this brittleness, the normalcharacteristic of the harder steels, has constituted a serious obstacleto the utilization in gyratory or cone crushers of those metals whichhave the .highest wear resistance.

It is a purpose of the present invention to overcome the drawback of thebrittleness of harder metals by employing facing parts of a metal ofvery high resistance to wear, these facing parts being secured to orsupported on or against backing or supporting parts of a differentmaterial having greater tensile strength and adequate resistance tofracture. Thus 1 provide, in effect, a composite crushing or wear-takingmember in which I am able to employ for the wearing surface parts metalof adequate hardness for maximum wear resistance, while providing, also,a backing or supporting or connecting structure of a different material,with the necessary tensile strength to stand up under the pounding, wearand stress inevitable in the operation of a crusher.

As will appear below, a wear-taking body or wearing part is cast frommetals or alloys having originally, or by treatment, a high Brinnellhardness. Preferably, such parts or bodies are arranged as sections orsegments about the crushing cavity, as will 2p ear below.

BRIEF DESCRIPTION OF THE DRAWINGS Referring to the drawings:

FIG. I is a partial, vertical, axial section through a type of crusherhaving a normally fixed bowl and a head gyrated within and beneath it;

FIG. 2 is a plan view on a different scale, illustrating a plurality ofwear-taking segments, such as are shown in the lower half of FIG. 1;

FIG. 3 is a partial axial section, on the same scale as FIG. I, througha variant form of wear-taking segment and backing; and

FIGS. 4 and 5 are partial sections illustrating variant structures.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Like parts are indicated bylike symbols throughout the specification and drawings.

Referring to the drawings, 1 generally indicates a head which may begyrated, the supporting and gyrating structure of the head formingthemselves no part of the present invention. 2 indicates a bowlstructure normally fixed in relation to the crusher as a whole. It may,for example, be mounted on a circumferential frame, or on a supportingring mounted on a circumferential frame, the details of the frame andsupporting connection being not of themselves part of the presentinvention. 3 indicates a bowl liner which does not illustrate myinvention, but is shown simply as a typical surrounding bowl linerwithin or against which the wearing parts may, in accordance with myinvention, operate. 4 is any suitable securing means for holding thebowl liner 3 in its normal crushing position.

Turning to the lower part of FIG. I, I illustrate a frustoconic ring orsupport 5 which may extend entirely around the head I, and is shown asabutting a lower outer portion thereof. Under various circumstances itmay be permanently, or semipermanently, secured to the head 1, or it maybe made removable from the head I, and simply dropped down on it.'

What is important is that it extends circumferentially about a lowerportion of the head 1 and provides an abutment for receiving,positioning and supporting the below-described crushing segments. Itwill be understood that the ring 5 may be of any suitable material whichwill resist cracking or breaking, and which is not expected to receivecrushing wear. The crushing wear is to be taken entirely by thesubsequently described segments.

Turning to the segments, 6,6 indicate typical segments which may be of amaterial of suitable hardness, far harder than the material of support5, and far harder than the hitherto used manganese steel. A wide rangeof materials maybe employed. It will be realized, of course, that myinvention is not limited to any specific metal mix or alloy, except sofar as l limit myself to them in the appended claims.

As will be clear from FIG. 2, I provide for the use ofa multiple ofsegments 6, which, together, extend circumferentially about the lowerpart of the gyrated head I. The segments may be initially connected bypieces or necks 6 of restricted diameter. These can be broken, when thesegments are in place, or may simply be left in place. I illustrate aninterval 6" between adjacent segments, this interval being somewhatexaggerated in FIG. 2, to emphasize the fact that the segments areseparate parts, are not connected to each other, and, being alreadyseparated, are freed of the tendency to crack or break, which a closed.ring of the same metal would have. As a matter of convenience, each ofthe segments, as shown in FIG. 1, has a large or thick wear-takingportion, indicated as 6 with a wearing surface 6. 6 indicates anabutment portion, which is remote from the wearing surface 6" and whichreceives any suitable locking or thrusting ring or member, or members,7, the details of which do'not form part of the present invention. As anexample, a frustoconic ring 7 may be formed to abut the .portion 6" ofall of the segments 6 simultaneously, and its upper end may be suitablysecured to the gyrated shaft, not shown, of the headI, in such fashionas to subject the abutment portion 6" to a downward and outward thrusteffective to force the surface 6' against the ring 5. Thus eachof thesegments 6 is held in position in relation to the ring 5, with itssurface 6 opposed to the opposite wearing surface of the bowl liner 3.As the head I is gyrated, for example, by the gyration of whatever shaftis employed with it, the segments 6 move toward and against the bowlliner 3 and subject the material fed from above to a crushing ordisintegrating nip. The entire wear is taken by the wearing surface 6"and before the segments 6 are so deeply worn as to subject the ring 5 towear they are removed from the crusher and replaced. It is a simplematter to handle them when separated, since each of these segments is ofrelatively small weight, as it extends only onequarter of the way aroundthe head or crushing cavity. They may be cast with the connectors 6'.With this use of segments the material of the segment 6 is tailored orpicked precisely to suit the crushing stresses and strains to which thesegments are subjected, while the material of the ring 5 is chosen toprovide adequate backing, without cracking or breaking. If desired, anysuitable backing material 8 may be used or inserted in the gap betweenthe upper outer surface of the ring 5 and the lower surface of eachsegment 6.

It will be understood that the specific formation, dimensions, shape anddetails of the various parts may be widely varied. I may, for example,as shown in FIG. 3, employ embedded members of reinforcing material,such as steel of high tensile strength and resistant to fracture. Suchreinforcing material is shown at 10 in FIG. 3, within the enlargedportion ofa segment 9. In the form of FIG. 3, it will be understood thata multiple of segments is employed, and that there is independentreinforcement 10 for each of the segments, there being preferably noreinforcing connection between segments. Preferably, the reinforcementis placed at a substantial distance from the wearing surface 9, so thatthe reinforcement will not be exposed until the wearing part 9" of thesegment 9 has been substantially worn down. Then the segments may beremoved and replaced. The securing means may, for example, be as shownin FIG. I, with a suitable counterpart of the conic thrust ring 7.

It will be understood that the shape of the circumferential support 5maybe widely varied. I illustrate in FIG. 3, for example, acircumferential support 11 which has an outer, upper extension 12. Asshown in FIG. 3, the wearing pan 9" of the segment 9 is shaped in orderto provide a zone of separation 13 which may be filled by any suitablebacking, whether of a soft metal or of a plastic. The specific backingdoes not of itself form part of the present invention. As shown in FIG.1, a clearance is shown at 1'' between segments and head.

As an indication of the wide variations which may be made in shape ofparts, while within the spirit of my invention, I illustrate, also, FIG.4, in which a ring 15 extends all the way about the crushing head, withan abutting portion I6 which may receive, for example, the equivalent ofthe ring 7 of FIG. 1. 17 indicates a segment or insert which may bepositioned on or about the ring I5. Any suitable number of these insertsmay be employed, for example, the four shown in connection with FIG. 2.A clearance space 19 may be filled with any suitable backing. Acircumferential ring I8 may, if desired, be employed. It fon'ns part ofthe composite wear-taking structure and may be welded to the ring 15. InFIG. 4, rings 15 and 18 may extend entirely around the head and be heldupon it by a suitable thrust against the portion l6, the members I7constituting inserts, a plurality of which are put in the position inwhich the insert 17 is shown in FIG. 4. In the form of FIG. 4 the entiregroup, including a removable backing ring I5 and the ring 18, may beapplied and removed together, resting upon the exterior of a head suchas is shown at I in FIG. I. In this instance a preformed wear-takingstructure is provided with the rings 15 and 18 of breakage-resistantmaterial and the insert 17 of harder wear-taking material, an adequatenumber of them being used, for example, the grouping of four, as shownin FIG. 2. If desired, they may be initially connected.

FIG. 5 again indicates a composite element in which the wear-takingmember 20, of hard material, is anchored to a circumferentiallyextending structure, indicated at 21, which may have anchor openings.This structure forms part of a removable assembly, but whereas itextends continuously about the crushing cavity, the inserts or wearingparts or segments 20, of hard or brittle wear-taking metal, areseparated from each other, for example, as shown in FIG. 2, though theymay be initially cast or applied with connectors such as are shown at 6A suitable backing may be installed in the clearance space 25.

It will be realized that whereas I have described and shown a practicaland operative device, nevertheless, many changes may be made in size,shape, number and disposition of parts without departing from the spiritof my invention. I therefore wish my drawings to be taken as in a broadsense illustrative or diagrammatic rather than as limiting me to myspecific disclosure herein.

The use and operation of the invention are as follows:

I have shown various forms of a wear-taking assembly for use with agyrated crusher head. In each of these assemblies a wear-taking part, orparts, of hard material is exposed to wear, but is backed up by acircumferentially extending supporting or joining structure of a softermetal, more resistant to breakage. I find it important in all cases tohave a plurality of hard wear-taking segments or parts exposed to thematerial passing through crushing cavity. These parts perform thecrushing or reducing function and receive the wear or abrasioninevitable to such crushing. One reason for casting the wearing elementsin the form of separate parts or segments, and for mounting thesesegments adjacently but individually, is that in foundry practice it hasbeen found that high stresses develop internally in a complete ringduring the casting and cooling process. In some cases these stresses maynever be removed, with the result that a highly stressed casting isinstalled in a crusher. Additional stresses are applied to the circularcasting in service, with the result that failure often results, evenwith comparatively low crushing forces. It is the employment of theseseparate parts or segments which makes it possible to use a more brittlematerial, since the castings are not subjected to the high internalfoundry stresses which are inherently characteristic of the ring shape.If, in the course of crushing, a piece of tramp iron or uncrushablematerial enters the crushing cavity, the segment or part directly incontact with the tramp iron will receive the impact. Since therelatively brittle material used is not cast in a ring, this tramp ironcontact with a single segment directly affects only the particularsegment involved. Where a ring is used, of brittle material, thedeformation caused by contact with the tramp iron extends around thecircumference, and creates stresses which may result in failure of theentire member.

In each of the forms herein shown the separate parts or segments of hardmaterial, which do not form a closed ring or cone, are backed up by thesofter inetal parts which form a circumferentially extending backing,which are protected from wear, and which are of a characteristic toprevent cracking, breakage, or rupture. So far as necessary, I alsoemploy a backing which may be of soft metal, such as zinc, or which maybe of a plastic material, such, for example, as is sold under the tradename "NORDBAK" by the assignee of the present application. Such abacking is illustrated at 8 in FIG. I, at 13 in FIG. 3, at 19in FIG. 4,and at 25 in FIG. 5.

As examples of materials to be employed for the crushing segments orparts I may mention pearlitic, carbidic white cast iron, or martensitic,carbidic, chrome-nickel alloyed cast iron, sometimes known as NII-IARD".Castings from such metal may be brittle and hard, but they haveexcellent wear characteristics. The material of which the backing partsor rings are formed is not critical. What is simply essential is that ametal or material be employed which will not readily crack or rupture.Since it is the purpose of the invention to have the hard wearingportions take the crushing contacts, the backing structures do not haveto have high wear-taking characteristics.

Whereas, in FIG. 1, I illustrate the bowl liner 3 as a single,circumferentially extending part, it will be understood that I may, if Iwish, sectionalize the ring and separate it into a backing portion andwear-taking portion of different hardness and characteristics. It isthought unnecessary to go into details as to such modifications of thebowl liner.

Iclaim:

I. In a composite unitary wearing assembly to serve as a replaceablewearing part for the crushing chamber of a crusher of the gyratedhead-type, a circumferential, generally continuous backing member of amaterial of predetermined hardness and strength, formed and adapted toextend about and to be rcmovably supported in the crushing cavityagainst a part of the crusher, and a plurality of closely approachingsurface members of a metal of substantially greater hardness and wearresistance than the material of the backing member, the surface membersbeing mounted on, bonded to, and supported by the circumferentialbacking member so as to form a unitary element therewith, and beingshaped and positioned to take substantially the entire crushing wear ofthe material being crushed by the crusher, the surface members being ofa substantially brittle material of great hardness as compared to thematerial of the backing member.

2. The structure of claim 1 further characterized in that the assemblyis constructed and adapted to be mounted on the gyrated head of acrusher.

3. The structure of claim 1 further characterized in that the surfacemembers are individually bonded to the backing member by a nonmetallicbacking material,

4. In a wearing part for the crushing chamber of a crusher of thegyrated head type, a circumferential annular backing member extendingcompletely about a lower, outer part of the crushing chamber. and aplurality of closely approaching surface members of a metal ofsubstantially greater hardness than the material of the backing member,the surface members being positioned upon and seated against thecircumferential backing member and being shaped and positioned to takesubstantially the entire crushing wear of the material being crushedwhen the crusher is being operated. the surface members each having apositioning surface directly engaging the backing member along a planein the direction of application of the crushing stress and each havinganother surface spaced from a backing surface on the backing member ingeneral parallelism with the crushing face of each surface member, and afiller of relatively soft material interposed between the backingsurface of the backing member and the adjacent surface of each surfacemember, whereby to cushion the surface members in relation to thebacking member.

5. The structure of claim 4 further characterized in that the wearingpart is constructed and adapted to be mounted on the gyrated head of acrusher.

6, The structure of claim 4 further characterized in that the fillerindividually bonds the surface members to the backing member and is of anonmetallic material.

